Retinopathy of Prematurity – (ROP)

Description and implications

  • Retinopathy of Prematurity (ROP) is most often seen in premature
    infants who received oxygen therapy, although it does occasionally occur
    in full-term infants. The severity of ROP may range from minimal ocular
    damage with no vision impairment to complete retinal detachment and scaring
    that can cause total blindness. The extent of the condition depends on
    many factors, including the length of time the infant received oxygen
    and the amount of oxygen that was administered. There is no effective
    treatment, however careful monitoring of the blood levels of premature
    infants and the use of oxygen only when necessary to prevent death or
    brain damage significantly reduced the number of students affected by
    this condition. ROP was a major cause of vision impairment in the 1940s
    and 1950s when unlimited oxygen was given to premature babies. It is becoming
    an important cause of vision impairment again in the 1990s as more low-birth
    weight infants are surviving
  • ROP almost invariably affects both eyes within a few weeks
    of birth, particularly when the birth weight is less than 1200 grams and
    where the concentrations of oxygen is in excess of 30 per cent. The oxygen
    causes a sequence of events in the immature retinal vessels:
    i) vasoconstriction which leads to vaso-obliteration during exposure to
    oxygen: in the presence of too much oxygen, the immature blood vessels
    in the retina spasm and close down
    ii) vasoproliferation after removal from the oxygen: when the supplemental
    oxygen is withdrawn, the area where the vessels have closed down becomes
    anoxic. To supply the anoxic tissue, new vessels quickly invade from the
    adjacent retinal tissue. These invading vessels are abnormal and leak,
    causing oedema (swelling) of the retinal tissue. Later this area becomes
    fibrotic which leads to scarring which may, in a small number of premature
    babies, cause detachment of the retina
  • depending on the extent of the vascular damage to the retina,
    the student may have areas of normal or near-normal vision. If these areas
    are in or near the macula (the area of the retina responsible for fine
    discrimination tasks eg reading), the student will be more able to access
    printed material. Where visual fields are fragmented, the student will
    have difficulty with visual closure (eg interpreting maps and diagrams).
    Severe ROP can result in total blindness
  • associated conditions may include microphthalmus (a small underdeveloped
    eye), moderate to severe myopia (near sightedness), amblyopia (lazy eye)
    may result if the student’s refractive errors are significantly different,
    glaucoma, cataracts and uveitis are common secondary problems
  • a significant number of these students will have brain damage
    which may result in learning difficulties.

Suggested teaching strategies

  • ensure that all staff working with the student, including replacement
    teachers and volunteers, are aware of the vision impairment and its educational
    implications
  • if the student has a refractive error in addition to the ROP,
    glasses may be prescribed
  • students may require magnification of reading and graphic material.
    This can be achieved by bringing the material closer to the eye, or by
    the use of prescribed magnification aids – hand held magnifiers or reading
    spectacles for near work or monocular/miniscope for distance viewing.
    A closed circuit television (CCTV) may be found to be beneficial especially
    in the primary years when students tend to move around less. It may be
    necessary to enlarge some or all of the students work, but it is usually
    preferable for the student to use a hand held magnifier competently as
    this skill will assist the student to operate independently with other
    out-of-school tasks
  • if the student has patchy fields, enlargement may not be of
    assistance. Enlargement of reading material will mean that fewer letters
    are seen in the restricted visual field. If lowered acuity necessitates
    enlargement, ensure that the optimum print size is used (ie the minimum
    print size which can be sustained), and implement a program to gradually
    decrease the print size managed
  • students with ROP may need good lighting for reading tasks.
    A lamp may be necessary
  • the use of shiny surfaces (eg white boards, shiny paper for
    flashcards or worksheets, shiny table tops) should be avoided as they
    can reflect light toward the student’s eyes
  • always use a clean chalk board with white or yellow chalk or
    white board with black marker. Use a consistent layout when presenting
    information on a board eg homework is always found on the far right hand
    side of the board
  • reading material often needs to be modified eg tactual diagrams,
    audio format, braille, enlargement. For young students it may be sufficient
    to bring reading material close to the eyes
  • utilise high contrast materials eg black texta for writing,
    textas for drawing, coloured paste, using clear bold illustrations to
    cut around
  • bold lined paper may assist
  • reading strategies may need to be developed to compensate for
    a narrowed field of view. With a reduced field, the student will see only
    a few words or letters at a time. Visual memory and the ability to chunk
    information can be a helpful strategy
  • students with patchy fields may need to look using a less affected
    area of their retina. This is called using their eccentric vision
  • tracking and scanning techniques will require training and
    practice
  • depending on the amount of residual vision, and the amount of
    remaining field of vision, the student with ROP may be very clumsy and
    have mobility difficulties
  • field disturbances may mean that the student must turn his/her
    head to see beyond his/her field of view
  • students will benefit from desktop demonstrations ensuring visual
    access eg correct handwriting formation of a new letter, science experiment
    etc
  • organisational skills may require development. Developing efficient
    organisational skills will assist a student with a vision impairment eg
    having a large pencil case to store pens, calculator and visual aids;
    setting aside extra time to collect any equipment required; allowing extra
    time to complete visual tasks etc
  • additional verbal description and verification may be required
    to ensure the student has access to his/her environment eg describe a
    new classroom or excursion venue, provide verbal praise etc. The student
    with a vision impairment may miss a smile of encouragement
  • the use of a personal computer (eg laptop) may be of great
    assistance to a student with a vision impairment as an alternative to
    handwriting and to reduce visual fatigue. Software is available for enlarging
    text and graphics, including icons, menus etc. Voice output is available
    for both IBM and Macintosh computers. Individual assessment of the needs
    of each student is essential. Keyboarding skills should be taught in primary
    school
  • strategies to reduce vision fatigue should be considered eg
    appropriate visual rests may include listening to audio tapes both for
    information and relaxation
  • students with a vision impairment often need to be taught social
    skills using a direct teaching approach. Modeling appropriate social behaviors
    can be difficult when you cannot see them accurately
  • students with a vision impairment may need additional orientation
    and mobility training
  • understanding and acceptance of the student’s vision impairment,
    individual learning modes and work production methods (eg braille, computer
    etc) may be facilitated through carefully planned simulation activities
    and class education programs
  • ball games may be difficult. Ensure that teachers are aware
    of this and provide as many auditory cues as possible
  • reading environmental signs eg street signs may cause difficulties
  • where the student cannot access printed material, braille tuition
    may need to be introduced, This will require careful introduction and
    timing
  • students with ROP are sometimes small in stature and staff
    and students may be disposed to treat them as if they are younger than
    their chronological age. It is important to encourage independence and
    age appropriate behaviour at all times.

Note: Students with significant residual ROP changes can be at
risk of further damage to the retina including retinal detachment. Some
retinal specialists advocate that they be warned against undue exertion
and contact sports.

These notes were made by the staff of the Statewide Vision Resource Centre.
They are general statements and may not apply to all students with this
condition.